S. Chang, H. Ow, B. Yoon, W. Wang
Aramco Americas,
United States
Keywords: optical sensor, chemical sensor, rapid sensing, paper-based diagnostic devices
Summary:
Timely detection and quantification of oil field chemicals in reservoir fluid is utmost to efficient reservoir management. However, the reservoir fluid analysis requires labor-intensive separation/extraction processes to remove interferents, and sophisticated laboratory instruments that must be operated by trained specialists. These monitor and surveillance operations are therefore difficult to implement in remote regions. Paper-based analysis and detection platforms requiring simple, portable hardware have the potential to provide near real-time analysis at the well-site. However, for the trace level optical detection, the background fluorescence from either fluorescent optical brightener or indigenous lignin in the paper/cellulose fibers, significantly limits the sensitivity. The study details a low-cost portable various paper-based diagnostic devices that enable rapid on-site chemical analysis of reservoir fluids. In addition, it specifies the challenge of using paper-based devices for trace level fluorescent chemical analysis and how this is effectively addressed with paper-based substrates. The study will also discuss specific functionalization chemistry on the paper substrates to enhance sensitivity of the diagnostic devices and outline fluorometric and/or colorimetric read-out and quantification methods using a time-resolved fluorescence camera.